Heat-conducting tube



Aug. 10 1926. 1.595563 T. E. MURRAY HEAT CONDUCTING TUBE Filed June 20,1924 j v [NI 5A" 70R fiat Z447 I M 4 A TTURNEY Patented Aug. 10, 1926.

UNITED STATES THOMAS- E. MURRAY, or BROOKLYN, NEW YORK.

HEA'1 -CONDUCTIN G TUBE.

Application filed June 20, 1924. Serial No. 721,180.

In certain prior applications, Nos. 642,427

filedMay 31, 1923, and 642,725 filed June 1, 1923, I have described acertain hollow con-- struction for walls and other parts of boilers orheaters and made up of tubes of rectangular, circular or irregularcross-section with fins or flanges extending lengthwise thereof so as toprovide a heating surface exposed to the heating gases greater than thesurface which is in contact with the water or other fluid in the tube. v

The present invention provides a unit from which such boiler walls andthe like may be built. The accompanying drawings illustrate embodimentsof the invention.

Fig. 1 is a horizontal section of a side wall of a boiler built withthetubular units ofthe invention; Fig. 2 is a perspective View partly insection showing the ends of certain oblong tubes and their connectionwith a header 5 Figs. 3 to 8 are plans of various forms of unit made inaccordance with the invention. Referring to Fig. "1, the boiler wall ismade with an inner lining or screen comprisingtubes 1 with lateral finsor extensions across the spaces between the tubes. On the outside ofthis screen is the wall of the boiler structure which may be of anyusual or suitable material and which as illustrated comprises refractoryblocks or bricks 3 outside of which are tiles 4 of non-conductingmaterial and an outer shell 5 of sheet metal. The longitudinal finsextend throughout such portions of the length of the tube as may bedesired according to the design of the boiler and throughout the zonewhere their conducting efi'ect is desirable. As shown in Fig. 2, theyextend to a header 6 into which the upper ends of the tubes areintroduced.

' and with convex ends which are welded to the circular tubes at 8. Fig.3 illustrates a structure in which a number of circular tubes andfiattubes are in a single structure. Instead of this, the

welded edge to edge wall may be made in units which are separate fromeach other, each'unit comprising a circular tube with an extension atone side; or a tube having extensions welded to both sides of it and thenext circular tube being plain.

According to Fig. 4, the extension comprises a rolled shape having twoopposite diverging sides 9 welded at-their ends to the circular tube asat 8 and connected at their outer edges by a portion 10.

According to Fig. 5, a known rolled shape comprising two divergingmembers 11 is welded at the inner edges thereof, these members beingconnected at their outer edges to a broad flange 12. y

According to- Fig. 6, the tube 1 has welded directly to it at 8 a plate1.3 with a flange 14 at its outer edge, and a separate plate 15 is setin the space between the flange 14 and the tube. This sort of doubleextension may be provided at each side of the tube as shown at the leftand a similar extension may be provided 'at the inner'face of the tube,that is, the face exposed to the fire,

as for the right hand tube.

According to Fig. 7, the extension comprises a looped sheet 16, theinner edges of,

which are brought together and welded to the tube as at &

According to Fig. 8, a similar construc tion is obtained by uniting twosegments each having a semi-circular central portion 17 with flat sideportions 18 on the ends of which are flanges 19, which flanges arewelded together along joints 20. Since this flanged tube, thusconstructed, is exposed to the pressure within the tube, it is advisableto fasten theflanges 18- together, and this is accomplished byspot-welding or otherwise welding them at 21.

In all the above cases, it will be observed that the lateral extensionsfrom the tubes are of double thickness, so that only one face of themetal isexposed to the destructive 'eflect of the fire. The inner facesof the looped constructions of Figs. 4 and 5, for

main tubes 1' may carry the water and the lateral tubular extensions 7may carry air .or other fluid to.be heated. Where flat tubes 'Fig. 6.Although I have referred to each unit as consisting of a single tubewith an extension at each side of it, yet it may oonsist of a pluralityof tubes with proper extensions. For example, Fig. 3 may be taken toillustrate a unit consisting of two tubes 1 with a connecting hollowweb; a

4 number of such units being used separately to build u a wall withcontacting or overlapping e ges. A full description of the method of useof these units and of the best methods of welding the arts together isdescribed in another app ication which I have filed concurrentlyherewith, Serial No. 715,369 filed May 23, 1924. As described in saidapplication also, the lateral exten sions applied to the tubes canadvantageously be made of special metal or specially coated to resistdeterioration by the heat. But this is not so important in the presentcase where only one face of the metal is exposed to the heat.

Though I have described with great particularity of detail certainembodiments of myinvention, yet it is not to be understood therefromthatth'e invention is restricted to the particular embodimentsdisclosed. 'Various modifications may be made by those skilled in theart without departure from- '1. A heat conducting unit for boilers com-I prising a tube for water with an external lateral extension lyingsubstantially parallel to the tube and exposed to the heating gases,said extension being composed of two parts, one of which lies in frontof the other and shields a face of it from the heating gases.

2. A heat conducting unit for boilers comprising a tube for water withan external hollow lateral extension lying substantially parallel to thetube and exposed to the heating gases.

3. A heat conducting unit for boilers comprising a tube for water withan external lateral extension lying substantially parallel to the tubeand exposed to the heating gases, said extension being composed of twoparts welded to the tube and one lying in front of the other.

4. A heat conducting unit for boilers comprising a tube for water withan external hollow lateral extension welded to said tube and lyingsubstantially parallel thereto and exposed to the heating gases.

5. A heat conducting unit for boilers comprising a tube for water withan external lateral extension consisting of a second tube welded to thefirst and lying substantially parallel thereto and exposed to theheating gases.

6. A heat conducting unit for boilers comprising a tube for water withan external lateral extension consisting of a second tube flattened andwelded at an end of its longer diameter to the first tube and lyingsubstantially parallel thereto and exposed to the heatlng gases.

In witness whereof, I have hereunto signed my name.

THOMAS E. MURRAY.

